Day: February 17, 2010

Buy stock in hot glue, this project corners the market on the stuff. [Leafcutter John] uses the hot goop as his water-proofer of choice when building an underwater microphone (also known as a hydrophone). By installing a couple of piezo elements on one lid of a tin can he is able to record some amazingly clear audio. This is aided by a pre-amp inside the metal enclosure. By cleaning off the clear coating from the inside of these steel can parts, he was able to solder the seams to keep the water out. In the end, coins are added for ballast and any remaining space is completely filled with hot glue.

He’s got a handful of example recordings on his project page. Here’s an what a running faucet sounds like from under water:

What sounds like a sex-toy is actually the reason these musicians haven’t been practicing. Marv is the MIDI actuated robotic vibraphone built by [Tim O’Keefe], [Michael McIntyre], and [Brock Roland]. Every key has a solenoid positioned below it. The beauty here is that other than four small holes used for mounting, the vibraphone hasn’t been altered at all. The solenoids are positioned on the outside edges of the instrument but there’s also a hidden secret. A set of dampers have been installed between the two ranks of keys. These are used to stop dampen ringing keys after the note should have stopped.

These guys have exhibited some beautiful craftsmanship. Check out the videos after the break and if you have the chance, see Marv in person at BarBot 2010. If you do attend that robot extravaganza don’t miss your chance to enjoy a breast-pump actuated cocktail.

This track is awful, someone skip it! This project does just that with a wave of your hand. A laser beam shines across a room and, when obstructed, it sends a command to an iPod. One wave pauses playback, two waves skips to the next track, and a constant obstruction jumps backward one track.

They’re using a textile-compatible electronics platform called Schemer. This is the first time we’ve run across this product which uses a modular system to connect devices via a 1-wire communications bus.

3 breast pumps, a Meggy jr RGB (slightly modified) and copious amounts of alcohol. This sounds like a typical weekend at HAD headquarters, but it is in fact the parts list for the Drink Making Unit by Evil Mad Scientist Laboratories. Created for the upcoming Barbot 2010 event, this unit is a cocktail mixer. Load 3 liquids in, program the Meggy and you can push a button to dispense. We are pleased to see how much they modified off the shelf components to make this happen. Yes, there could be major improvements like mixing, more liquid reservoirs, and a better cooling system, but we think this thing is pretty slick.

[Kenneth Finnegan] quenches our clock-a-day compulsion with his Arduino based binary timepiece. The clock uses a 5×7 LED matrix as a display and shows month, day, and time. He sourced a DS3232 real-time clock which automatically compensates for temperature to achieve very accurate time keeping. We like the super-cap circuit he added to keep the RTC running if the power is cut.

Is an Arduino overkill here? Well, the code is certainly not filling the 16k available on the ATmega168. At $4.32, the $1-2 you could save by using a lower-grade chip is not worth having to rewrite the code developed during prototyping. [Kenneth] also mentions that these projects usually only hang around for a few weeks before they’re re-purposed for the next endeavor.

Take a look at [Kenneth’s] superb hardware walk through in the video after the break. If you’re a fan of clean breadboarding, he’s also made a time-lapse of the circuit building process.

[Andreas] found that his home theater PC would not boot one day. Oddly, if he disconnected his HDMI cable from his TV, it would boot fine. While most of us would have dug into the PC, he realized that it was a signal from the TV that was incorrect. Luckily, LG had included a full schematic with the TV. What he was able to figure out, using a home made snooper was that the EDID eeproms had somehow become corrupted. Not to worry, [Andreas] slapped together a full blown I2C interface and prepared to reprogram them with the correct data. He noticed, however, that the eeproms were write protected. On a whim, he decided to write to them any way and found that it was successful. He has some theories as to why they were writable, but says that he doesn’t want to pull the TV back apart to confirm.